gelding vs wild horse

gelding

noun
  • A castrated male horse. 

  • Any castrated male animal. 

wild horse

noun
  • A feral horse. 

  • An untamed horse. 

  • A member of the species Equus ferus, sometimes excluding the domesticated horse. 

How often have the words gelding and wild horse occurred in a corpus of books? (source: Google Ngram Viewer )